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Sandy is complaining that the car is "faster" than it was a little while ago. Yes, complaining. I haven't done anything to it, and the only thing I can think of is that the weather is 40F colder than the last time she took the car to work.

Before I moved out here, I was asking people if I needed to do anything to the Z in respect to the weather (from San Diego to Potomac, MD). The only response other than all weather tires (which I never found much use for) was "winter is great for turbocharged cars, it's like adding an intercooler!" (the 280ZXT had none). I never much noticed this in the Z, as taking it out in the winter was never such a good idea anyways. But more recently, I read an article by Honda Tuner about the Zex intercooler fogger kit. They recorded a 65-hp increase when using it on the dyno.

Now, liquid nitrous oxide is a lot colder than 29F. I am wondering whether it's possible she's noticing something like that. I personally don't get the car up to WOT that often, and when I do, it's hard to notice any objective difference (really f'n fast is just really f'n fast, most of the time). It's also possible I should cut back her crack intake.

It's just the cool air! Tell her to relax and enjoy it!

Yep, cold air helps our cars a lot! People with UTEC's on their Subaru's notice it since the UTEC does not compensate for the colder air coming in. Conequently, they usually have a cold weather and a hot weather map.

Sabre wrote:Yep, cold air helps our cars a lot! People with UTEC's on their Subaru's notice it since the UTEC does not compensate for the colder air coming in. Conequently, they usually have a cold weather and a hot weather map.

Compensate? You mean the stock ECU actually changes its map based upon the temperature of the intake air? It would seem to me that a MAF just measures the amount of air (regardless of density) flowing through it. Or did I miss something?

colder air = denser air = more O2 molecules = more f4st4rrr

avriette wrote:Compensate? You mean the stock ECU actually changes its map based upon the temperature of the intake air? It would seem to me that a MAF just measures the amount of air (regardless of density) flowing through it. Or did I miss something?

Yes, the stock ECU does make adjustments for a colder/denser charge of air. It is very sesitive, but also pretty adaptive. Turbo cars will spool quicker and boost higher in cold air. The ECU can modify boost (adjust the wastegate), as well as pull timing and add fuel to compensate. This is why IC sprayers help so much during hot weather.

^^^ To add to what Darrin said, our MAF's are actually MAF's AND temperature sensors. My Hydra doesn't use the MAF reading, but it does use the intake temperature to compensate for the different intake temperatures.